It is known to provide a single reinforcing timber rib down the centre of a surfboard. The surfboard is formed from a blank that is cut in half lengthwise of the board. The rib is set between the two halves which are then bonded back together and fiber glassed.
The rib is arranged in a vertical configuration and provides rigidity and additional strength to the board along the centre line, where a surfer's feet are placed. However, any flexing of the board, such as while riding a wave, generates a twist around the rib and through the length of the board, which can adversely effect performance.
Another form of reinforcement is to place carbon fiber strips along rails of the board and fiber glass over the rails during the final production phase of the board. The reinforced rails provide increased strength along the sides of the board but not at the ends of the board and, importantly, not where the surfer's feet are usually placed.
Another disadvantage of the side rail reinforcement is that carbon fiber can be damaged during production, shaping and handling of the core before the fiber glass is applied and that can compromise the strength of the reinforcement.